A Fait Accompli? An Empirical Study into the Absence of Consent to Third-Party Tracking in Android Apps


Konrad Kollnig and Reuben Binns, University of Oxford; Pierre Dewitte, KU Leuven; Max Van Kleek, Ge Wang, Daniel Omeiza, Helena Webb, and Nigel Shadbolt, University of Oxford


Third-party tracking allows companies to collect users' behavioural data and track their activity across digital devices. This can put deep insights into users' private lives into the hands of strangers, and often happens without users' awareness or explicit consent. EU and UK data protection law, however, requires consent, both 1) to access and store information on users' devices and 2) to legitimate the processing of personal data as part of third-party tracking, as we analyse in this paper.

This paper further investigates whether and to what extent consent is implemented in mobile apps. First, we analyse a representative sample of apps from the Google Play Store. We find that most apps engage in third-party tracking, but few obtained consent before doing so, indicating potentially widespread violations of EU and UK privacy law. Second, we examine the most common third-party tracking libraries in detail. While most acknowledge that they rely on app developers to obtain consent on their behalf, they typically fail to put in place robust measures to ensure this: disclosure of consent requirements is limited; default consent implementations are lacking; and compliance guidance is difficult to find, hard to read, and poorly maintained.

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@inproceedings {274431,
author = {Konrad Kollnig and Pierre Dewitte and Max Van Kleek and Ge Wang and Daniel Omeiza and Helena Webb and Nigel Shadbolt},
title = {A Fait Accompli? An Empirical Study into the Absence of Consent to {Third-Party} Tracking in Android Apps},
booktitle = {Seventeenth Symposium on Usable Privacy and Security (SOUPS 2021)},
year = {2021},
isbn = {978-1-939133-25-0},
pages = {181--196},
url = {https://www.usenix.org/conference/soups2021/presentation/kollnig},
publisher = {USENIX Association},
month = aug

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